Tanking as an awareness test
For tanks, there are a few things you need to understand. The first is, no matter how well geared you are, no matter how skilled you are at the new active mitigation tanking, you will eventually die without healing. Therefore, if you are the type of tank who likes to run ahead and pull constantly, never stopping to let the healer drink or checking on his or her mana, knock it off. Am I saying you can't pull fast? No. I'm saying always check on your healer before you pull. You don't have to say anything to her or him. Set the healer as your focus, take a gander at his or her mana before you pull six mobs or a boss. It's not hard.
Secondly, as a tank, you have to be aware of the new fixed mana pools that healers are working with. Healers can't get bigger mana pools by stacking stats, so you need to be very aware of your environment. Are you standing in pools of fire, or in front of a cone attack that you can easily sidestep? Don't. Make use of your new active mitigation and step out of the way. Don't stand there, take a ton of damage, die, and curse your healer's incompetence when all you had to do was take one step to the left and the boss' channeled ability would have missed you entirely. Tanking is as much about damage management as it is threat now, it's not just your job to stick a ton of mobs to your face it's also your job to do as much as you possibly can not to die once you have them there.
Healing and the art of standing safely
For healers, I know that healing can be stressful, but you can't just slam heals everywhere. I've seen a lot of healers die on Xin the Weaponmaster because they stood there and died to one of Xin's many, many annoying ways to turn the floor into a garden of death. It's better to let DPS die than die yourself trying to heal them if they fail to take the environment into account, and if a tank seems to be taking a ton of damage you can ask if they're getting out of fire, moving to avoid cone attacks, etc. Don't be rude about it, of course, but they may not know that a particular attack can be sidestepped.
DPS does not mean deaths per second
For DPS, please stop running ahead and pulling mobs while we're dealing with a pull. I don't even understand why you guys do that, but I see it a lot and it's a bad idea. As DPS, you have no idea if your tank's big threat moves are on cooldown, if they have the resources needed to absorb or deflected the kind of additional damage they'll take if they manage to pull the new mobs off of you, or if they're like me and they won't taunt off of you when you do that. Yeah, I know you didn't like dying. I didn't like having to deal with an extra pull because you wanted to go faster. I know my limits. You don't. In general there is never a good reason for a DPS to be ahead of the tank anyway. Why are you up there? The best possible result is that you end up waiting for the tank.
Using a knockback ability should be your very last choice. If the tank is dead, maybe. If there's no nearby trash that a knockback is going to end up aggroing and bringing to the group. If the knockback is like Dragon Roar you may be saying "Well, it doesn't knock them very far" but you need to be careful not to put mobs behind the tank. Mobs behind the tank can't be dodged, parried or blocked.
How to Pull
Don't stand in death. It's true for tanks, it's true for healers, it's even truer for you. A boss can still be killed with a dead DPS, it's just much harder. Also, if you have an ability that will mitigate or absorb damage or heal you, use it. Don't just wait for a heal. Anything you can do to personally help with your survival is a good ability to use.
Finally, every group needs to learn the difference between different kinds of pulls. A Misdirect pull's threat is temporary, but on a long enough cooldown (30 seconds) so that it's usually not going to wear off before the tank generates genuine threat. If you see a tank taunt or otherwise pull and then run around a corner, it's called a corner pull, and it's often the only way some tanks can move stubborn casters into a pile to be tanked. Don't run ahead and start nuking the target and prevent it from moving, you're defeating the entire purpose of the corner pull. Let the mobs come to the tank and then kill them.
I know I'm forgetting a host of annoying behaviors from all roles, so I throw the gates open to you, gentle readers. What should groups know to do, and not to do?
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